DESIGN AND CONSTRUCTION OF SEALING THERMAL LINE COVERS

FOR CLOSE-EASY TERRAFÉRTIL COMPANY SA "

Danny Sanmartín

UNIVERSIDAD TECNICA DEL NORTE

Ibarra / Ecuador

dannyjaviers@gmail.com

I SUMMARY

This research arises from the need for

resolving the sealing system covers the

company closes easy Terrafertil SA,

especially in the area of production and

packaging, on the difficulty you have when

not to use a sealing process continuous and

adequate, the same as is done manually

using sealing pedal, whose performance is

not commensurate with production.

This machine comprises a control that is

based on synchronization of multiple drive

mechanisms, this new system is to replace

an electromechanical control that requires

excessive maintenance due to mechanical

and electrical wear suffered machines. The

system reduces the time of commissioning

of the machine and enables the operator to

change the production of one product to

another, because it is not necessary to

perform mechanical adjustments to give the

length of the bag sealed.

II INTRODUCTION

The company Terrafertil SA has come to

represent one of the pioneers at the national

and international level, in the category of

small and medium enterprises, whose social

and economic activity is the development,

production, and marketing of nuts and dried,

intended for human consumption, ensuring

their safety at each of its processes.

For the process, now sealed in the

business of used sealing pedal, as shown in

(Figure 1.1), with a throughput of 15 to 20

cases per minute and having a productivity

so high it is difficult to control the tightness

and aesthetic sealing sleeve to sleeve.

Figure: Current process sealing

For the preparation of each of these

products the company is governed by

several standards. They have even come to

implement good manufacturing practices

BPM's, in each of its processes, which

begins with the careful selection of raw

materials, in which providers are subject to

evaluations of quality character.Then the

transformation of matter that is channeled

and implemented by the department of

quality control, which are responsible for

releasing batches of both raw material and

finished product.

For product packaging doy pack bags

are used which are prefabricated sleeves

and are equipped with a closed-easy on top

as detailed in Figure 1.2.

Figure: Composite Covers

III PROBLEM

Heat sealing is the most critical in the

food processing industry, as this depends

on the life of the product, but there are

industries where this process is still done

manually causing cosmetic problems and

even more if affects the production time .

In the company the process of sealing

covers closed-easy sealing is done by foot,

where the pressure and temperature of

sealants are not controlled, therefore can

not guarantee tightness and product

presentation.

It is producing a revolution with new

technologies, of which increasing accuracy

and reliability in the different processes

obtain therefore the sealing of covers for

closers easy wealth will improve productivity

in the company, include that, thanks to new

technologies, pollution control and

occupational health is growing.

Developing this project a real need for a

process to renew the local industry solution

will be provided, as well as demonstrating

the machines and processes they can be

improved with technology and with high

business vision.

IV GENERAL PURPOSE

Design and build a thermal sealing

machine covers online closers easy to meet

the needs of production, the company

Terrafertil SA

V SPECIFIC GOALS

Determine the variables

involved in the sealing process to

have a previous design of the

prototype.

Design and select different

mechanical, electrical, and control

elements to meet expectations

initially raised design.

Build and assemble each of

the elements of the machine.

Perform the various tests and

adjustments for optimum

performance of the sealant.

VI THEORETICAL BASIS

SEALING TECHNIQUES

For sealing plastics some methods used

in industry, including you have used:

Heat sealing

Ultrasonic sealing

Adhesive sealing

HEAT SEALING

The heat seal is to seal two overlapping

portions of material, by using heat

generated by heating elements on hot rods

joining the portions of material.

Among its features are:

Simple in implementation

and use.

It does not require

sophisticated machinery and

controls.

It is low cost of

implementation.

Does not use solvents or

fillers.

Reliable and resistant seal.

It requires prior niquelinas

time for heating and bars.

ULTRASONIC SEALING

The ultrasonic sealing is an innovative

technique in which the frequency of

ultrasound is used for bonding together two

parts of a molecularly materials

Among its features are:

Very fast process.

High control and status

monitoring process.

Rugged and reliable sealing

without visual imperfections.

Technology low energy

consumption very friendly with the

environment.

Does not use solvents or

fillers for sealing.

Waterproof packaging.

It does not require preheating

of the machine.

SEALING ADHESIVE

This sealing process involves the use of

glues and adhesives for bonding plastic

parts and forming the sheath.

Among its features are:

Sealing materials compatible

with the type of glue.

Sealing is not completely

waterproof.

Times moderate process.

Low power consumption.

Use of adhesives, silicones

or resins sealing.

Resistant seal without

possibility of re use of packaging.

POLYMERS

The Polymers are macromolecules

(geneeralmente organic) formed by the

union of smaller molecules called

monomers, macromolecules body case are

polyethylene and ethylene monomers

correspond.

Figure: Composition of a polymer

To be aware of where arises

polyethylene, which is the raw material of

prefabricated sleeves have a chart where

you can see that belongs to thermoplastics.

Figure: Classification of polymers

PROPERTIES OF LOW DENSITY POLYETHYLENE

Low density polyethylene is the raw

material of the container to be used for the

presentation of products, so you are going

to see some necessary characteristics of

these plastics for analysis.

Table: Mechanical properties of low density polyethylene

MECHANICAL PROPERTIES

E elastic modulus (N /

mm 2) 200

Tensile modulus (GPa) 0.1-0.3

Tensile strength (MPa) 5 - 25

Breaking strength (N /

mm 2) 8 - 10

Elongation at break

(%) 20

Table: Thermal characteristics of low

density polyethylene

THERMAL PROPERTIES

Specific heat (JK -1 kg -1) 1900-2300

Expansion coefficient (× 10 6 K -1) 100-200

Thermal conductivity at 23 ° C (W

/ mK) 0.33

Softening point (° C) 110

Crystallization temperature (° C) 105-110

Table: Electrical characteristics of

polyethylene

ELECTRICAL PROPERTIES

Dielectric constant at 1

MHz 2.2 to 2.35

Dissipation factor at 1

MHz 1-10 x 10 -4

Dielectric strength (kV

mm -1) 27

Surface resistance (ohm /

sq) 1013

Volume resistivity (ohm

cm) October 15 -10 18

DESIGN PARAMETERS

The company Terrafertil SA as producers

of nuts and dried seek to obtain very good

results with the sealing, save time and also

have a greater production, which must meet

the following design requirements.

FUNCTIONAL

Tasks to be performed

Manual entry of the cases.

Horizontal feed of the

sleeves.

Dragging covers the area of

the sealing rollers by means of

silicone bands.

Sealing sleeves that are fed

to the machine.

Rear drag of the sheath to

maintain stability by silicone roller.

Help the packing stage to go

through a conveyor belt.

Dispatch bag for subsequent

packaging.

Design parameters

Packaging type seal:

Prefabricated covers Doy pack.

Operating temperature: 100-

160 ° C

Product ambient temperature

seal 18 ° C.

Energy supply must be

single-phase 110 Vac, 60 Hz.

Adjusted to facilities (small

and medium businesses),

dimensions being lightweight and

versatile.

As for the control parts is

purely electric and easy exchange

and replacement parts.

304 stainless steel

construction materials and sanitary

grade, suitable for contact with food

according to international standards.

OPERATIONAL

It should be easy to move

and adjust.

Make it easy disassembly.

Design for the operator to

unskilled personnel.

Ergonomically designed for

personnel safety.

Easy installation and

operation, easy understanding.

BUSINESS

The dimensions of the

machine must match the spaces in

the micro, small and medium

enterprises.

Shelf life: about 10 years.

Use of materials or parts

preferably local suppliers.

Little use of degradable

materials ensure life.

DEVELOPMENT OF ALTERNATIVE

DESIGN

In the formulation of design alternatives

you have a bank options then be chosen

strategically both the sealing mechanism

and the drive mechanism for moving the

equipment, alternative choice will be that by

studying in a decision matrix and the

appropriate option will be in a higher score

is obtained.

SEALED

Induction sealing (option A)

Sealing jaws (option B)

Sealing rollers (option C)

Ultrasonic sealing (option D)

Table: Decision matrix sealing system

TECHNICAL

CHARACTERISTICS

DESIGN ALTERNATIVES

TO B C D IDEAL

Security 20 20 25 18 30

Low initial cost 4 8 12 1 fifteen

Silent 8 5 7 8 10

Low cost of operation and maintenance

1 4 4 1 5

Good performance 4 3 4 4 5

Small size and light 2 1 4 4 5

Ease of manufacture 2 1 4 3 5

Ease of service and replacement parts

5 3 4 3 5

Ease of Operation 4 3 5 4 5

Components readily available on the market

2 4 4 2 5

TOTAL % 52 52 73 48 100

Most suitable for the design of the

sealing system, alternative is sealed by heat

rollers with a percentage of 73%. The

second option is the induction sealing or

jaws.

TRACTION MOTION

Drive gear (option A)

Chain drive (option B)

Traction band (option C)

Table Decision matrix drive system

TECHNICAL

CHARACTERISTICS

DESIGN

ALTERNATIVES

TO B C IDEAL

Security 21 26 25 30

Low initial cost 6 12 12 15

Silent 4 6 7 10

Low cost of operation and maintenance

2 4 4 5

Good performance 1 4 2 5

Small size and light 2 4 3 5

Ease of manufacture 1 4 3 5

Ease of service and replacement parts

4 3 5 5

Ease of Operation 4 4 4 5

Components readily available on the market

2 4 2 5

TOTAL % 47 71 67 100

The alternative best suited to the

requirements of traction by means of

chains, option B, because a percentage of

71% as second choice having tensile bands

was obtained.

CAPABILITIES

Figure : Case prefabricated

Equation: Formula to find the amount of sealed bags per minute

Q =Rs

Ls + Ef

Where:

Ls = Length of the sealing sleeve = 16 cm =

0.16 m

Ef = Space between cover and cover = 15

cm = 0.15 m

Rs = Stroke sealed in a minute: 10 m

Q = Number of sealed bags per minute

Substituting we have:

Q =10 m

0,16 m + 0,15 m

Q =10

0,31= 32,2581 = 32 fundas por minuto

STRUCTURE DESIGN

The structure is the major part in the

design as this depends on the team does

not collapse, to perform the calculations

necessary to draw up a table like Table, in

which the weight of each element of the

machine is detailed

Table: Weight of machine components

DESCRIPTION QTY.

WEIGHT

(Kg.)

LOAD

(N)

MOTOR -

REDUCER

Sealing

mechanism

CONVEYOR

BELT

TOTAL

1

1

1

2

17.32

2,559

21,987

19.62

169.9

25.1

215.69

SIZE

HIGH: 1350 mm

Width: 750 mm

LENGTH: 450 mm

MAXIMUM EFFORT VON MISES

In analyzing the Von Mises stress with a

value of 10.63 MPa it is obtained as shown

in Figure.

Figure: Maximum stress of Von Mises

Namely:

σ. ≤ Sy

Where:

𝜎 . Effort = von Mises

Sy = Is the yield strength of the material

10,63 MPa ≤ 310 MPa

It can be concluded that the Von Mises

stress is less than the yield strength of the

material, which ensures that the system will

collapse and is well dimensioned.

SAFETY FACTOR OF STRUCTURE

Structure for 304 stainless steel is used,

with the features:

Sy = 310 MPa and Sut = 620 MPa

As previously detailed, we proceed to

find the FDS in the structure; For this we

turn to the equation.

Equation: Safety factor

σ. =Sy

n

Source: (BUDYNAS, 2008)

Where:

n= Safety factor

Sy = Creep resistance of the material

σ.= Effort von Mises

So:

n =310 MPa

10,63 MPa

n = 29,16

THERMOSTAT

For the development of this project, in

terms of temperature control one Watlow

controller 935A-1CC0-000R series will be

used, see (Figure 4.4) is a temperature

controller with countdown timer for

industrial, commercial or scientific

applications .

Figure 4.4: Watlow temperature controller 935A-1CC0-000R

It can be seen below in figure, the

controller features:

Figure 4.5: Features Watlow 935A

pyrometer

TEMPERATURE SENSOR

In this case a thermocouple type J see

figure, which is only two wires of different

materials joined at one end and the other

connects to the pyrometer, when applying

heat in the attached tip is used comes a

differential voltage on the order of millivolts

it varies proportionally with

temperature.Thermocouple type j is fully

compatible with the pyrometer Watlow,

allowing readings of 0 to 750 ° C. Then see

characteristics table.

Figure: Thermocouple type J

Table: Characteristics of type J thermocouple Termokew

PARAMETER VALUE

Material Iron -constantán

Temperature

range

0-760 ° C

Tolerance ± 2.2 - 0.75%

Covering Stainless 304

Diameter 3/16

SPEED CONTROL AND

ADJUSTMENT

For controlling machine speed you will

have chosen a purely adaptive controller for

a DC motor see Figure, based on a triac

circuit which consists of voltage variation

and in turn proportional to this speed.

Figure: Variable speed

VIII CONCLUSIONS

It complies with the main

objective of the project is the design

and construction team, managing to

meet expectations and initially set

parameters.

With the implementation of

online heat sealing process

efficiency by 40%, and in turn

increased the production rate

increased by 75% in the company.

It should take into account

before executing the project's

progress, conduct a preliminary

study of the variables of temperature

and speed of sealing gaskets to

seal, as these variables constitute

an essential pillar in the design.

304 stainless steel used is an

excellent material because it is able

to withstand the stresses to which

the machine will be subject, as well

as their properties are in an aseptic

and suitable material to work with

food.

While the continuous sealing is

designed to seal bags with easy

gauge closes 94 μ, it can adapt to

your work in any other case smaller

or larger caliber.

In the field of design must have

the tools necessary to make a

prototype which in turn provide the

necessary guarantees, in this case it

was decided by two software

computer aided design such as

Autodesk Inventor and Solid Works

that were be helpful for

implementation and validation of

each of the pieces, simulations and

corroboration of measures.

IX RECOMMENDATIONS

Keep in mind when making a

previous design, the materials and

spare parts needed to manufacture

the equipment can be easily

achieved in the industrial market,

and thus prevent or calculated the

dimensions assigned to each item

are inconsistent with the available

material .

Ensure that the materials used

in the manufacture of machine

governed based on standardized

food regulations and internationally

accepted to avoid possible

contamination of the product and

ensure the safety and cleanliness of

the process.

To run a project to implement a

machine in the industry, it is

necessary to conduct a preliminary

economic analysis, where you will

realize whether or not prematurely

make the project feasible for both

the designer and the company.

To validate the design data is

necessary to rely on software

design and modeling, simulations

both to generate manufacturing

drawings.

Perform maintenance work

following one by one the activities

proposed in the maintenance plan

to prevent premature damage to the

machine and maintain a longer life.

X REFERENCES

Askeland, DR (2004). The

Science and Engineering Materials

(4th. Ed.).Mexico: Editorial

Thomson.

Basantes, E. (September 18,

2014).The conversion

package.Retrieved from

//www.elempaque.com/temas/Mas-

potencia-con-el-sellado-por-

induccion-de-la-Super-Seal-

Touch+4094062

Budinas R., NJ (2008).

Mechanical engineering design

Shigley. Mexico: McGraw-Hill /

Interamericana.

Incropera, I. (1999).

Fundamentals of heat transfer.

Mexico City, Mexico: Prentice Hall.

Kreith, F. (1986). Heat transfer

principles (s / e). Madrid Spain.

Larburu, N. (2003). Handbook

machines. Magallanes, Spain:

Thomson.

MOTT, RL (2006). Design of

machine elements (4th.

Ed.).Mexico: Editorial Pearson.

NORTON, RL (2005). Machine

Design (3rd. Ed.).Mexico: Editorial

Mc Graw Graw Hill.

Verdugo, C. (2010). Design

and implementation of monitoring

and control system for the machine

cutting and sealing covers tepack.

Prior to obtaining engineering

degree in electronics, EPN. Quito.

WATLOW. (2014). Watlow

temperature controllers 935 series.

In Watlow, User Manual (pp.1-58).

Mexico.

Solution, N. (12 August

2014).Solutions package.Obtained

from

http://www.novamart.com/tienda/ind

ex.php/empaque/selladoras/sellado

ras-de-banda/selladora-de-banda-

vertical-continua.html

Surtirodamientos. (16 August

2014).Transmission and

power.Retrieved from

http://www.surtirodamientos.com/tra

nsmision-y-potencia/

TERMOKEW. (11 August

2014).Design and manufacture of

thermocouples.Retrieved from

http://www.termokew.mx/